Floor cleaning machine and method for operating a floor cleaning machine

ABSTRACT

A floor cleaning machine is provided, comprising a suction unit device, a suction bar which is operatively connectable, or operatively connected, to the suction unit device for fluid communication therewith, a holder which releasably holds the suction bar, a fixing device for releasably fixing the suction bar at the holder, and an overload protection device which is associated with the suction bar, wherein the overload protection device comprises at least one rotational bearing by way of which the suction bar is rotatable at the holder relative to the holder when an overload situation occurs.

This application is a continuation application of international application number PCT/EP2019/080603 filed on Nov. 7, 2019, the entire contents of which are incorporated herein by reference in its entirety.

The present disclosure relates to the subject matter disclosed in international application number PCT/EP2019/080603 filed on Nov. 7, 2019, which is incorporated herein by reference in its entirety and for all purposes.

BACKGROUND OF THE INVENTION

The invention relates to a floor cleaning machine, comprising a suction unit device, a suction bar which is operatively connectable, or operatively connected, to the suction unit device for fluid communication therewith, a holder which releasably holds the suction bar, a fixing device for releasably fixing the suction bar at the holder, and an overload protection device which is associated with the suction bar.

The invention further relates to a method for operating a floor cleaning machine.

WO 2011/057232 A2 discloses a release mechanism for a suction bar in a floor cleaning machine.

Suction bars are disclosed, for example, in EP 2 559 367 A1, WO 2014/191024 A1, WO 2015/086115 A1, JP 05280785 B2, EP 3 178 363 A1. DE 20 2014 011 047 U1 discloses a suction nozzle.

DE 10 2011 055 445 A1 discloses a cleaning apparatus comprising a suction channel.

EP 2 814 370 B1 discloses a floor cleaning machine comprising a release squeegee.

DE 10 2009 029 956 A1 discloses a self-propelled pick-up sweeper.

DE 196 11 371 A1 discloses a suction apparatus attachment for wet cleaning of surfaces.

SUMMARY OF THE INVENTION

In accordance with an exemplary embodiment of the invention, a floor cleaning machine is provided which permits an optimized cleaning operation to be effected.

In accordance with an exemplary embodiment of the invention, the floor cleaning machine comprises a suction unit device, a suction bar which is operatively connectable, or operatively connected, to the suction unit device for fluid communication therewith, a holder which releasably holds the suction bar, a fixing device for releasably fixing the suction bar at the holder, and an overload protection device which is associated with the suction bar, wherein the overload protection device comprises at least one rotational bearing by way of which the suction bar is rotatable at the holder relative to the holder when an overload situation occurs.

In the event that the suction bar, when operating in a cleaning mode, collides against an object or even snags onto an object, an overload situation can occur. In the solution in accordance with the invention, in certain overload situations, the suction bar, via the at least one rotational bearing, can perform an avoidance movement by rotating at the holder before it in particular falls away therefrom. Damage to the floor cleaning machine and to the object is thereby avoided.

In particular, the at least one rotational bearing has no function during normal cleaning operation. It only functions in a (certain) overload situation to enable the suction bar to perform an avoidance movement relative to the holder.

The at least one rotational bearing does not necessarily have a function in every type of overload situation. For example, the situation may arise where the cleaning machine is passing through a passageway that has room for the body of the machine to pass therethrough but leaves no room for the suction bar. When the suction bar collides against the boundaries of the passageway on either side of it, then the configuration of the overload protection device (overload protection) is such that the suction bar (when in such position that both sides thereof simultaneously collide against the boundaries) will fall off without prior rotation.

It is advantageous for the at least one rotational bearing to have an axis of rotation with at least one of the following:

-   -   the axis of rotation is transverse, and in particular         perpendicular, to a plane of support of the suction bar on a         floor to be cleaned;     -   the axis of rotation is transverse, and in particular         perpendicular, to a wheel axis of the floor cleaning machine;     -   the axis of rotation is in spaced relation to a central plane of         the suction bar, which central plane lies between a first end         face and a second end face of the suction bar, relative to a         fixing position of the suction bar at the holder;     -   the axis of rotation is oriented at least approximately parallel         to a central plane which lies between a first end face and a         second end face of the suction bar, relative to a fixing         position of the suction bar at the holder.

The fixing position is a position of the suction bar with respect to the floor cleaning machine which permits a proper cleaning operation and a cleaning run to be performed. Here, the suction bar sits (with its suction lips) on the surface being cleaned and can draw off excess fluid (which is dirt-laden in particular). By virtue of the corresponding orientation of the axis of rotation of the at least one rotational bearing, in the event that the suction bar collides against an object or in the event that the suction bar snags onto an object, an avoidance movement can be achieved in order to avoid damage to the floor cleaning machine and to the object.

In particular, the at least one rotational bearing, relative to a fixing position of the suction bar at the holder, is in spaced relation to a port for a suction conduit that is arranged at the suction bar, and/or is in spaced relation to a central plane of the suction bar which lies between a first end face and a second end face of the suction bar. A capability for rotation of the suction bar relative to the holder can thereby be achieved when an overload situation is encountered.

It is particularly advantageous for at least a first rotational bearing and a second rotational bearing to be provided, which second rotational bearing is in spaced relation to the first rotational bearing. With this arrangement, in the event of a collision to the left hand side or to the right hand side, a respective avoidance movement can be achieved. In particular, at least one of the following is then provided:

a first axis of rotation of the first rotational bearing and a second axis of rotation of the second rotational bearing are at least approximately parallel to one another;

-   -   a central plane of the suction bar which lies between a first         end face and a second end face of the suction bar, lies between         the first rotational bearing and the second rotational bearing,         relative to a fixing position of the suction bar at the holder;     -   the first rotational bearing and the second rotational bearing         are in a mirror-symmetrical arrangement about a central plane         which lies between a first end face end and a second end face         end of the suction bar;     -   a port for a suction conduit at the suction bar is located         between the first rotational bearing and the second rotational         bearing, relative to a fixing position of the suction bar at the         holder.

Thus, in particular, a symmetrical arrangement can be achieved which permits different avoidance movements for different overload situations to be performed by the suction bar.

In a configuration with simple construction, the suction bar comprises a support region for the holder and the holder comprises a contact region for the support region of the suction bar, in particular wherein in a fixing position of the suction bar at the holder, the suction bar is clampingly held to the holder via the contact region. This then provides a simple way of mounting or dismounting the suction bar with respect to the holder. A simple way is provided to fix the suction bar at the holder in a force-locking manner and/or in a form-locking manner. An overload protection device can be configured in a simple manner. The at least one rotational bearing can be implemented in a simple manner. In particular, a rotation of the suction bar relative to the holder can be implemented in an overload situation in which the contact region is in supportive contact with the support region and, hence, the suction bar still remains with the holder.

It is then particularly advantageous for the support region to have a planar contact surface and, in particular, for the contact region to have a planar contact surface for the support region. This provides a simple way of implementing the at least one rotational bearing.

In an embodiment having simple construction, the at least one rotational bearing comprises a wall which is arranged at the support region of the suction bar, wherein the wall defines a receptacle, and the at least one rotational bearing comprises a counter element which is arranged at the contact region of the holder, wherein, in a fixing position of the suction bar at the holder, the counter element is positioned in the receptacle. This provides a simple way of implementing the at least one rotational bearing when the fixing position of the suction bar at the holder is present. The at least one rotational bearing does not hinder mounting the suction bar to the holder and does not hinder dismounting the suction bar from the holder. The at least one rotational bearing can be formed with a minimized number of components.

In particular, at least one of the following is provided:

-   -   the receptacle is closed towards the support region of the         suction bar, and is in particular bounded by the support region;     -   the receptacle is open in a direction away from the support         region;     -   the receptacle is bounded by the wall in a direction away from         the holder, with respect to a fixing position of the suction bar         at the holder;     -   the receptacle is open towards the holder with respect to a         fixing position of the suction bar at the holder;     -   the wall has an arcuate shape;     -   the wall extends in an angular range of at most 180°;     -   the wall has a height of no more than 5 cm, and in particular of         no more than 3 cm, and in particular of no more than 2 cm.

Once the corresponding counter element is received in the receptacle, a rotational bearing is implemented. The arcuate configuration correspondingly provides a capability for rotation. By virtue of the wall's limited dimensions and/or by virtue of the upwardly and rearwardly open receptacle, the counter element also can be brought out of the receptacle when a certain overload situation is encountered. It is then possible, for example, for the suction bar to be fully released from the holder. This effectively prevents damage to collision objects or to the floor cleaning machine and the suction bar.

Furthermore, it is advantageous for at least one of the following to be provided:

-   -   the counter element has an arcuate shape on an end face that         faces towards the wall;     -   the counter element is formed as a finger;     -   the counter element is of planar configuration on an underside         thereof facing towards the support region of the suction bar;     -   the counter element is of planar configuration on an upper side         thereof facing away from the underside;     -   a height of the counter element between an upper side and an         underside is no more than 2 cm.

Thus, the at least one rotational bearing can be implemented with simple structure. The number of components required is minimized.

In an embodiment, the counter element bounds an indentation at the holder, with at least one of the following:

-   -   a fastening element of the suction bar is positioned in the         indentation when the suction bar is in a fixing position at the         holder;     -   the indentation has an arcuate boundary;     -   the indentation is bounded by a web on a side thereof facing         away from the counter element.

In this way, optimized positioning of the suction bar at the holder can be achieved.

In an advantageous embodiment, at least one tab is arranged at the suction bar for connection to the holder. An additional fixing region can thereby be provided. For example, this provides a simple way of preventing tilting of the suction bar relative to the holder (rotation of the suction bar relative to the holder). Furthermore, the tab can be utilized for positioning the suction bar at the holder, wherein, when the tab is correctly positioned, the at least one rotational bearing is automatically also established. Simple mounting and dismounting of the suction bar can thereby be achieved.

In accordance with a particularly advantageous exemplary embodiment of the invention, at least one tab is arranged at the suction bar for connection to the holder, and the at least one tab is formed as a hand grip for holding the suction bar.

The tab can then be used on the one hand for connection to the holder, and on the other hand, when the suction bar has been released from the holder, the at least one tab allows the suction bar to be held and carried by an operator.

In particular, the at least one tab is formed as a hoop. In this form, a weight saving is achieved. A simple way is provided for an operator to utilize the tab as a hand grip.

It is advantageous for the at least one tab to be centrally arranged with respect to outer end faces of the suction bar. With the tab configured as a hand grip, one can, in a sense, hold and carry the suction bar in a “balanced” orientation. Furthermore, this is a simple way of centrally providing tilt protection.

It is advantageous for the holder to comprise a holder receptacle for the at least one tab, wherein the at least one holder receptacle is configured for providing support to the tab. In particular, support against rotation of the suction bar relative to the holder can thereby be achieved.

In particular, at least one of the following is provided:

-   -   the holder receptacle is configured for providing support to the         at least one tab downwardly towards a floor to be cleaned;     -   the holder receptacle is configured for providing support to the         at least one tab upwardly in a direction away from a floor to be         cleaned;     -   the holder receptacle is open on an insertion side;     -   the holder receptacle has associated therewith an insertion ramp         on an insertion side.

By the provision of the downward and/or upward support, with respect to the holding of the suction bar by the holder, one or more points of support can be provided. This provides a simple way of achieving tilt protection in particular.

By the provision of the holder receptacle apertured on the insertion side, the at least one tab can be inserted into the holder receptacle. A simple mounting and dismounting are thereby possible.

By employing the insertion ramp, the insertion is facilitated. This provides an optimized useability for an operator.

Here, it is advantageously provided for the holder to comprise a contact region and for the suction bar to comprise a support region for said contact region, wherein the contact region is in spaced relation to the holder receptacle for the at least one tab. By way of example, the contact region is spaced in height. As a result of this, a further point of support is provided for the suction bar at the holder, and this provides a simple way of achieving tilt protection in particular.

It is advantageous for a housing box to be arranged at the holder, to which housing box is connected a suction conduit, and for the housing box, in a fixing position of the suction bar at the holder, to be positioned over a port for a suction conduit at the suction bar. The port for a suction conduit forms part of the suction bar. The housing box forms part of the holder. It is thereby possible for a suction conduit to remain with the machine. There is then no need for the suction conduit to reach all the way to the suction bar and be connected to the suction bar. In turn, the effect can thereby be achieved in a simple manner that, when an overload event occurs, the suction bar is partially or fully released from the holder without having to carry along with it the suction conduit (in the form of a suction hose in particular). The operative connection and fluid communication between the suction conduit and the suction bar is realized via the connection between the housing box and the port for a suction conduit at the suction bar. Furthermore, this results in a simple mounting of the suction bar to the holder and a simple dismounting therefrom.

In particular, at least one of the following is provided:

-   -   the housing box comprises a support surface for the suction bar;     -   the port for a suction conduit at the suction bar has an         inclined surface at which a port mouth is positioned;     -   the housing box is in spaced relation to at least one engagement         region of the fixing device;     -   a holder receptacle for at least one tab of the suction bar for         fixing the suction bar at the holder is arranged in the region         of the housing box;     -   the holder receptacle is spaced in height from the housing box;     -   in a fixing position of the suction bar at the holder, operative         connection and fluid communication between a suction conduit and         a port for a suction conduit at the suction bar is established,         and is established automatically in particular;     -   the holder receptacle conforms to the at least one tab such         that, when the suction bar is fixed at the holder with the at         least one tab received in the holder receptacle, the holder is         automatically positioned relative to the suction bar such that         the at least one rotational bearing is formed.

This makes for a simple mounting and dismounting of the suction bar. A simple way is provided to establish and release an operative connection and fluid communication between the machine and the suction bar, there being no need, for example, to additionally connect or disconnect a suction conduit from the suction bar.

In particular, then, a simple way is provided to automatically establish the connection when the suction bar is brought into its fixing position at the holder, and a simple way to automatically release the connection is provided.

If, in the event of an overload situation, the suction bar releases from the holder, the suction conduit can still remain with the machine.

It is advantageous for the fixing device to be configured such that in a fixing position of the suction bar at the holder, a force-locking connection exists between the holder and the suction bar. In the event that, when an overload situation occurs, a certain threshold value of the force loading is exceeded, which threshold value is then predetermined by the force-locking connection, a relative movement between the suction bar and the holder can be achieved in order to avoid the overload event and prevent damage to the floor cleaning machine and the object. The suction bar may be released from the holder.

Here, it can be advantageous for the fixing device to be configured such that, in a fixing position of the suction bar at the holder, a form-locking connection exists between the holder and the suction bar, and exists in addition to a force-locking connection in particular.

In particular, in accordance with an exemplary embodiment of the invention, the fixing device is configured such that, in a fixing position of the suction bar at the holder, a form-locking connection exists between the holder and the suction bar, and, in addition thereto, a force-locking connection exists between the holder and the suction bar.

This provides a simple way of mounting and dismounting the suction bar to and from the holder. Furthermore, this is a simple way for the suction bar to be able to release from the holder when an overload event occurs. In particular, this is a simple way of implementing a capability for rotation of the suction bar relative to the holder when an overload situation occurs.

In an embodiment having simple construction, the fixing device comprises at least one clamping element which is arranged at the suction bar and via which the holder can be clamped against the suction bar. This provides a simple way of mounting and dismounting the suction bar to and from the holder. A simple way to achieve a force-locking connection is provided.

It is then advantageous for the suction bar to comprise a support region for the holder and for the holder to comprise a contact region for the support region of the suction bar, and, here, for the at least one clamping element to be configured such that the contact region of the holder can be clamped between the support region and the at least one clamping element. In particular, this provides a simple way of achieving, through the clamping element, a clamped (and therefore force-locking) connection by transition from an open position to a closed position, or of releasing such clamped connection by reversing the process.

In particular, at least one of the following is provided:

-   -   the at least one clamping element is formed as a clamping lever,         and is formed as an eccentric lever in particular;     -   the at least one clamping element comprises a pivot element         which has a clamping surface and which is pivotably mounted on a         bearing element;     -   a bearing element of the at least one clamping element is         mounted for displacement on the suction bar;     -   a direction of displacement of the bearing element is oriented         transversely and perpendicularly to a pivot axis of the pivot         element;     -   the bearing element is supported on the suction bar via a spring         device, and is supported on an inner side of a support region of         the suction bar in particular;     -   a spring force of the spring device in a clamping position of         the at least one clamping element exerts a clamping force for         connecting the holder and the suction bar together in a         form-locking manner;     -   a direction of displacement of the bearing element and/or a         direction of force of the spring device is oriented at least         approximately parallel to an axis of rotation of the at least         one rotational bearing.

A force-locking connection can thereby be achieved which affords simple construction. A simple mounting and dismounting of the suction bar is possible.

It is advantageous if at least a first clamping element and a second clamping element are provided, the second clamping element being in spaced relation to the first clamping element. Clamping at spaced-apart fixing points can thereby be achieved. In particular, at least one of the following is provided:

-   -   the first clamping element and the second clamping element are         arranged outside of a central plane of the suction bar which         lies between a first end face and a second end face of the         suction bar;     -   the first clamping element and the second clamping element have         mirror symmetry about a central plane of the suction bar which         lies between a first end face and a second end face;     -   a port for a suction conduit is positioned between the first         clamping element and the second clamping element;     -   the first clamping element and the second clamping element are         located between a first rotational bearing and a second         rotational bearing.

In particular, a symmetrical arrangement can thereby be achieved which provides optimized fixing of the suction bar at the holder for a cleaning run, wherein a simple way is provided for an operator to mount and dismount the suction bar. Furthermore, a simple way is provided to achieve a force avoiding movement and release of the suction bar from the holder when an overload situation occurs.

It is advantageous for a form-locking connection to be present in addition to a force-locking connection. In particular, the fixing device then comprises at least one first form-locking element which is arranged at the suction bar, and at least one second form-locking element which corresponds to the first form-locking element and is arranged at the holder. In this way, for example, capabilities of movement for rotation of the suction bar at the holder can be predetermined. This results in an improved fixing.

In an embodiment, the at least one first form-locking element and the at least second form-locking element are arranged and configured such that, in a fixing position of the suction bar at the holder, when a force-locking connection is established between the suction bar and the holder, a form-locking connection with the at least one first form-locking element and the at least one second form-locking element is also established. In particular, establishing a force-locking connection automatically establishes a form-locking connection. An optimized fixing of the suction bar at the holder for a cleaning run is thereby achieved.

In an embodiment having simple construction, the at least one first form-locking element is arranged at the support region of the suction bar for the holder. In particular, this provides a simple way of establishing the fixing position of the suction bar at the holder while at the same time achieving a force lock and a form lock.

It is particularly advantageous for the at least one first form-locking element and the at least one second form-locking element to be configured to conform to one another such that, in a fixing position of the suction bar at the holder, a movement of the suction bar away from the holder in a blocking direction is blocked by a form lock, and is blocked in a single blocking direction in particular, with at least one of the following:

-   -   the blocking direction is at least approximately parallel to a         plane of support of the suction bar on a floor to be cleaned;     -   the blocking direction is at least approximately parallel to a         direction of insertion of at least one tab of the suction bar         into a holder receptacle of the holder;     -   the blocking direction is transverse, and in particular         perpendicular, to an axis of rotation of the at least one         rotational bearing;     -   the blocking direction is at least approximately parallel to a         chassis axis of the cleaning machine;     -   the blocking direction is at least approximately parallel to a         support region of the suction bar for the holder;     -   the blocking direction is transverse, and in particular         perpendicular, to a wheel axis;     -   the blocking direction is a unidirectional direction away from         the holder.

On the one hand, this provides a simple way of releasing the form-locking connection in a certain overload situation in order to permit a relative movement of the suction bar with respect to the holder also in the blocking direction. On the other hand, this provides a simple way of securing the fixing position in the blocking direction.

In particular, when a sufficiently large force is applied to the suction bar (in the event of a threshold force on the suction bar being encountered), the at least one second form-locking element can be released from the at least one first form-locking element. As a result, the form-locking connection provides a fixing which, although secure, is still releasable when an overload situation occurs.

In an embodiment having simple construction, the at least one first form-locking element is formed by an elevation at the suction bar and the at least one second form-locking element is a nose at the holder.

It is then advantageous for the at least one second form-locking element to have a blocking region for the at least one first form-locking element with which blocking region the second form-locking element is in contact against the first form-locking element when in a form-locking connection, and for the at least one second form-locking element to have an inclined plane for overriding the at least one first form-locking element. It is thereby possible, when a particular overload situation is encountered, for the second form-locking element to be brought over the first form-locking element in order to release the form locking relation therebetween. The suction bar can then partially or fully release from the holder in order to be able to avoid an overload event.

In particular, in an overload event, the suction bar rotates relative to the holder (via the at least one rotational bearing) and/or falls off the holder. What form of motion occurs depends on the particular overload situation, and in particular depends on how a suction bar collides against an object or snags onto the object.

In an embodiment, a checking device is provided to check for blockage at a suction path. It is thereby possible to recognize whether a blockage is formed at a suction path. The checking device may also recognize whether the suction bar has become released from the holder.

In particular, the checking device comprises at least one pressure sensor which is arranged at the suction path, and is arranged outside of the suction bar in particular. Via the at least one pressure sensor, a special situation can be detected by comparison against a characteristic curve family. It is also possible, for example, for a further pressure sensor to be provided at a fan.

The corresponding situation can be detected via a differential measurement. In the solution in accordance with the invention, the suction bar can partially or fully release from the holder when an overload situation occurs. If the pressure sensor is arranged outside of the suction bar, it can remain with the machine, and operative connection and signal communication with the machine automatically exists, even if the suction bar has become released.

In particular, the pressure sensor is arranged at a pressure conduit which can be connected, or is connected, to the suction bar, and is in particular releasably connected thereto. The pressure prevailing at the suction bar, and at the suction space of the suction bar in particular, can be detected via the pressure conduit. This can then be evaluated. Here, the pressure sensor need not be arranged at the suction bar but can be positioned outside of the suction bar.

It is advantageous for a port for a suction conduit at the suction bar to comprise a port for the pressure conduit. The pressure situation of a suction bar can thereby be measured, in a sense, at a distance from the suction bar.

In an embodiment, the pressure conduit is connected to a suction conduit.

This makes for a configuration having simple structure.

Furthermore, in accordance with an exemplary embodiment of the invention, a floor cleaning machine is provided, the floor cleaning machine comprising a chassis, a suction unit device, a suction bar which is operatively connectable, or operatively connected, to the suction unit device for fluid communication therewith, and a holder which is connected to the chassis and which holds the suction bar.

In accordance with an exemplary embodiment of the invention, a floor cleaning machine is provided which has advantageous cleaning properties.

In accordance with an exemplary embodiment of the invention, the floor cleaning machine comprises a chassis, a suction unit device, a suction bar which is operatively connectable, or operatively connected, to the suction unit device for fluid communication therewith, and a holder which is connected to the chassis and which holds the suction bar, wherein the holder has associated therewith a pivot joint via which the suction bar can be pivoted relative to the chassis, and a locking device is provided via which an adjusted pivot position of the suction bar relative to the chassis can be locked in place.

For an optimized cleaning result to be achieved, the suction bar (with its suction lips) must be oriented at an appropriate angle with respect to the surface being cleaned. Because of manufacturing tolerances, forces created during a cleaning operation, and differing requirements depending on floor type it may be advantageous to have variable presetting capabilities. By way of example, the suction bar, when in operation, can suck down on a floor surface and tilt somewhat in the direction of travel.

By virtue of the solution in accordance with the invention, an adjustable, lockable pivot position of the suction bar can be preset. The suction bar can then be adjusted, for example during mounting and/or during servicing and/or directly by an operator, in such a way that the optimized cleaning result is achieved.

By virtue of the solution in accordance with the invention, the floor cleaning machine is given enhanced variability in order to achieve an optimized suction result and also to permit adaptation to specific situations.

In particular, at least one of the following is provided:

-   -   a pivot axis of the pivot joint is oriented at least         approximately parallel to a plane of support of the suction bar         on a floor to be cleaned;

the pivot axis is oriented at least approximately parallel to a wheel axis;

-   -   the pivot axis is oriented transversely, and in particular         perpendicularly, to a direction of forward travel.

In the corresponding orientation of the pivot axis, an angular adjustment of the suction bar relative to the floor to be cleaned can be effected in order to achieve an optimized cleaning result. This provides a way of, for example, compensating for manufacturing tolerances. Forces generated during operation can be compensated for, or also adjustments can be made to suit a particular floor type.

It is in principle possible for the holder as a whole to be pivotably arranged at the chassis of the floor cleaning machine. The pivot joint is then a pivot joint between the chassis and the holder. Furthermore, it is also possible for the pivot joint to be formed between the suction bar and the holder.

The holder in an advantageous embodiment is formed of multi-part configuration and the pivot joint is integrated in the holder. It is thereby possible, on the one hand, for the holder to be fixedly connected to the chassis (wherein the holder may have capability for height adjustment relative to the chassis), and it is further possible for the suction bar to be connected to the holder, in particular via a support region thereof. In particular, this is a simple way of fixing the suction bar at the holder via a corresponding fixing device, and is a simple way of providing an overload protection device for the suction bar at the holder, as described above. The pivotability for angular adjustment for an optimized cleaning result is then fully integrated in the holder.

In an advantageous embodiment, the holder comprises a first part and a second part, wherein the second part comprises a contact region for the suction bar, the second part is connected to the first part via the pivot joint, and the second part is lockably pivotable relative to the first part. This provides a simple way of adjusting an angular position (pivotal position) of the suction bar relative to the chassis and relative to the floor to be cleaned. As a result, the corresponding pivot mechanism is simple in construction.

It is then further advantageous for the locking device to be connected (in particular directly connected) to the first part and the second part. This provides a simple way of adjusting and also locking a pivot position.

In an advantageous embodiment, the holder comprises a fastening part which is fixed at the chassis, and comprises an intermediate part which comprises the first part, wherein the intermediate part is oriented at an angle to the fastening part, the intermediate part is in spaced relation to the chassis, and an engagement region at the locking device for an operator is above an upper side or above an underside of the intermediate part. The term “above” as used herein means that a spaced relation exists to the upper side or to the underside and that the upper side or the underside bounds the corresponding space. This provides a simple way of making the locking device accessible to an operator in order to adjust and lock a particular pivot position of the suction bar. A space is present above the upper side or above the underside via which access can be had to the locking device, in particular with a tool.

In an embodiment having simple structure, the locking device comprises at least one pin element which is in spaced relation to a pivot axis of the pivot joint and is connected to the first part and the second part, wherein a height position of the at least one pin element (at the first part and/or the second part) locks a pivot position of the second part relative to the first part (and hence also an angular position of the suction bar relative to the chassis), in particular with at least one of the following:

-   -   the at least one pin element is formed as an adjusting screw;     -   the at least one pin element is guided by the first part and/or         the second part via threads and/or is provided with a counter         nut;     -   a compression spring device is located between the first part         and the second part in the region of the at least one pin         element and is supported on the first part and the second part.

This provides a simple way of adjusting and locking in place a defined pivot position of the second part with respect to the first part. Here, in particular, the at least one pin element is arranged in spaced relation to the suction bar and is positioned, for example, between a fastening part and a holding part of the holder. This provides for improved operator accessibility in order, for example, to be able to act on the at least one pin element via a corresponding tool.

In accordance with an exemplary embodiment of the invention, a method for operating a floor cleaning machine in accordance with the invention is provided, in which method the suction bar which is held to a holder can be rotated relative to the holder via the at least one rotational bearing when an overload event occurs.

The method in accordance with the invention has the advantages that have already been discussed in connection with the apparatus in accordance with the invention.

The following description of preferred embodiments serves in conjunction with the drawings to explain the invention in greater detail.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows, in top view, an exemplary embodiment of a floor cleaning machine in accordance with the invention;

FIG. 2 shows the floor cleaning machine of FIG. 1 in bottom view,

FIG. 3 illustrates, in perspective view, a suction bar of the floor cleaning machine of FIGS. 1, 2, showing it in its fixing position on a holder of the floor cleaning machine;

FIG. 4 shows a view similar to FIG. 3, although in the nature of an exploded view (the position of clamping elements at the suction bar corresponds to a position thereof when in a fixing position);

FIG. 5 illustrates the suction bar of FIG. 3, with clamping elements in such a position that the suction bar can be fixed on a holder;

FIG. 6 illustrates a top view of the suction bar of FIG. 3 and the holder, with suction conduit removed;

FIG. 7 shows an enlarged view of detail A of FIG. 6;

FIG. 8 shows a sectional view taken along line 8-8 of FIG. 5 (with clamping elements shown as being “opened”);

FIG. 9 shows a sectional view taken along line 9-9 of FIG. 7;

FIG. 10 shows a sectional view taken along line 10-10 of FIG. 7;

FIG. 11 shows a sectional view taken along line 11-11 of FIG. 7, wherein FIGS. 7 to 11 illustrate a fixing position of the suction bar at the holder;

FIG. 12 illustrates a view similar to FIG. 10, but showing an intermediate condition where the suction bar is about to release from the holder;

FIG. 13 shows an enlarged view of a portion of a holder receptacle of a holder for receiving a tab of the suction bar;

FIG. 14 shows a partial view of an exemplary embodiment of a suction conduit, shown as having a pressure conduit connected thereto;

FIG. 15 illustrates, in a perspective view, another exemplary embodiment of a holder, shown as having a suction bar held thereto;

FIG. 16 shows a sectional view taken along section plane B of FIG. 15; and

FIG. 17 shows a sectional view taken along section plane C of FIG. 15.

DETAILED DESCRIPTION OF THE INVENTION

An exemplary embodiment of a cleaning machine in accordance with the invention, shown in FIGS. 1 and 2 and in the partial views of FIGS. 3 to 14, designated therein by 10, is a scrubber suction machine. The cleaning machine 10 comprises a chassis 12. Arranged at the chassis 12 is a rear wheel device 14 having a left rear wheel 18 and a right rear wheel 20, relative to a direction of forward travel 16.

Also located at the chassis 12 is a steerable front wheel 22 which can be steered via a steering wheel 24 (FIG. 1).

In the exemplary embodiment as shown, the cleaning machine 10 is configured as a ride-along machine. A driver's seat 26 is arranged on the chassis 12. A driver sitting on the driver's seat 26 can access the steering wheel 24.

The cleaning machine 10 is formed of self-propelled configuration. To this end, the cleaning machine 10 comprises a motor drive such as an internal combustion engine or an electric motor.

Furthermore, (at least) one cleaning tool 28 is arranged at the chassis 12 (FIG. 2). For the case of a scrubber suction machine, the at least one cleaning tool 28 is a scrubbing tool. In particular, the scrubbing tool is provided with corresponding bristles.

In operation of the cleaning machine 10, the cleaning tool 28 performs a rotary movement about an axis of rotation 30. The axis of rotation 30 of the cleaning tool 28 is oriented in particular transversely to a wheel axis 32 of the rear wheel device 14. Here, the axis of rotation 30 can be oriented perpendicular to the wheel axis 32, or it can be inclined at a small angle, for example in the order of magnitude of 5° to 10°, from the perpendicular to the wheel axis 32.

The cleaning machine 10 comprises a motor drive for rotating the cleaning tool 28 about the wheel axis 32.

The cleaning machine 10 comprises an application device 34 for applying cleaning liquid onto a floor 36 that is to be cleaned (cf. FIG. 8). To this end, a nozzle device is arranged at the cleaning machine 10 via which cleaning liquid can be applied directly to the floor 36 to be cleaned. Alternatively or in addition, provision may be made for the cleaning liquid to be applied to the cleaning tool 28.

In particular, the cleaning liquid is water which may have added thereto a cleaning agent, for example a surfactant cleaning agent.

In particular, a tank device for cleaning liquid is arranged at the chassis 12.

In operation of the cleaning machine 10, provision is made for excess liquid to be sucked up from the floor 36. To this end, a suction bar 40 (suction squeegee) is held to the chassis 12 via a holder 38 (FIG. 2).

The cleaning machine 10 comprises a suction unit device 42 (cf. FIG. 1) having a fan and a fan motor. The fan has (at least) one impeller which is driven in rotation by the fan motor. A suction flow is thereby generated. The suction flow is applied to the suction bar 40 for taking up liquid from the floor 36 by suction.

The suction unit device 42 has associated therewith (at least) one dirty fluid tank 44 which receives fluid that has been sucked up. A separator may be provided.

The holder 38 is fixedly connected to the chassis 12. In particular, the holder 38 is arranged centrally relative to a width direction 46 of the chassis 12 (which is a direction parallel to the wheel axis 32).

In an embodiment, the holder 38 is arranged and/or configured such that a height position of the suction bar 40 relative to the floor 36 to be cleaned is adjustable. In particular, then, an operating position is provided in which the suction bar 40 sits on the floor 36 being cleaned, and a spaced-apart position of the suction bar 40 relative to the floor 36 is provided. In the spaced-apart position of the suction bar 40, the cleaning machine 10 can travel over a ground surface without the suction bar 40 touching the ground surface and undergoing unnecessary wear.

The suction bar 40 is arranged at the chassis 12 at a location downstream of the at least one cleaning tool 28 (relative to the direction of forward travel 16 in particular). In operation of the cleaning machine 10, cleaning liquid is applied to the floor 36 to be cleaned in the region of the cleaning tool 28. The downstream suction bar 40 is used for later pickup of excess liquid, subsequent to a cleaning operation performed on a particular area of the floor surface traversed by the cleaning machine 10.

In the cleaning machine 10, the suction bar 40 is arranged in the region of a rear end 48. Here, the rear end 48 faces away from a front end 50, wherein the front wheel 22 is positioned in the region of the front end 50. The suction bar 40 is also arranged downstream of the rear wheel device 14.

It is alternatively possible for the suction bar 40 to be arranged upstream of the rear wheel device 14, relative to the direction of forward travel 16 (and thereby to be arranged downstream of the at least one cleaning tool 28).

The holder 38 (cf. FIGS. 3 and 4 for example) comprises a fastening part 52 by which it is fixed at the chassis. Here, as mentioned above, the fixation can be fixed or with capability for height adjustment.

The fastening part 52 is located at an intermediate part 54. In particular, the fastening part 52 is oriented at an angle to the intermediate part 54, which angle is, for example, of the order of 150°.

Located at the intermediate part 54 is a holding part 56 which serves to releasably fix the suction bar 40.

The fastening part 52 is fixedly connected to the chassis 12 or is located at a height adjustment device which is connected to the chassis 12 and, in particular, via which the suction bar 40 can be lowered onto the floor 36 that is to be cleaned.

The holding part 56 is oriented transversely to the intermediate part 54. A width of the intermediate part 54 in a width direction is smaller than a corresponding width of the holding part 56 in that direction. The combination of intermediate part 54 and holding part 56 is T-shaped.

The holding part 56 comprises a contact region 58 for the suction bar 40. The suction bar 40 comprises a corresponding support region 60. The contact region 58 can be placed upon the support region 60. In particular, in a fixing position 62 of the suction bar 40 at the holder 38, in which position the suction bar 40 is fixed at the holder 38 for suction mode of operation, the suction bar 40 is clamped against the holder 38 via the contact region 58. This will be further elaborated below.

By way of example, the contact region 58 has a planar contact surface 64 for the support region 60 of the suction bar 40 (cf., for example, FIG. 9).

In an exemplary embodiment, the holding part 56 is formed with a flat configuration. Here, a surface of the holding part 56 opposite the contact surface 64 is, at least in portions thereof, of a planar configuration.

At a middle portion of the holding part 56 is connected a housing box 66. The housing box 66 is open towards the contact surface 64 and is open towards a front side 68. It has opposed side walls 70 which are formed of triangular shape. It has the open side thereof that faces towards the contact surface 64 closed by a lid 72. The lid 72 is oriented at an acute angle 74 to the contact surface 64 (cf. FIG. 11). The acute angle 64 is, for example, of the order of 25°.

A height of an interior space 76 of the housing box 66 increases continuously towards the front side 68.

A connecting piece 78 is arranged at the lid 72 of the housing box 66. Connected to the connecting piece 78 is a suction conduit 80 which is operatively connected to the suction unit device 42 for fluid communication therewith. The suction conduit has been omitted for clarity in FIGS. 6, 7, 11.

The suction conduit 80 is a machine-side suction conduit 80. It is not connected to the suction bar 40 directly but via the housing box 66. The housing box 66, along with the connecting piece 78 and the suction conduit 80 connected thereto, forms a machine-side connection of the suction unit device 42 to the suction bar 40.

When the suction bar 40 is removed from the cleaning machine 10 upon release of its fixing position 62, or when it releases from the cleaning machine 10 following an overload situation (as will be described in more detail below), the suction conduit 80 remains with the cleaning machine 10, and, here, remains with the housing box 66 in particular, while a corresponding suction pathway is disconnected from the suction bar 40, i.e., the operative connection and fluid communication therebetween ceases to exist.

The suction bar 40 comprises a port 82 for the suction conduit 80 which functions as a counter part to the housing box 66. This will be explained in more detail below.

The holder 38 comprises, at the holding part 56 thereof, in spaced relation to the contact region 58, a holder receptacle 84 (FIGS. 11, 13). The holder receptacle 84 serves to receive (at least) one tab 86 of the suction bar 40. The holder receptacle 84 is open towards a front side 88 which in the fixing position 62 faces towards the suction bar 40. It is closed on all other sides. The holder receptacle 84 comprises a wall 90 which has a rear wall 92 a opposite the front side 88. It further comprises a bottom wall 92 b which is oriented transversely to the rear wall 92 a. It has a cover wall 92 c which is in spaced relation to the bottom wall 92 b. The cover wall 92 c is in particular parallel to the bottom wall 92 b.

The holder receptacle 84 is closed at its sides by opposed side walls (not visible in the drawing).

The holder receptacle 84 has dimensions that conform to those of the tab 86. The tab 86, when in the fixing position 62, extends into a corresponding opening 94 of the holder receptacle 84 (cf. FIG. 13 in particular). Here, the opening 94 is formed between the rear wall 92 a, the bottom wall 92 b, the cover wall 92 c and the corresponding side walls. In particular, the holder receptacle 84 is configured such that it forms a positioning aid for locating the suction bar 40 at the holder 38. Accordingly, little play is permitted to the tab 86 within the opening 94. Once the position of the tab 86 is established in the opening 94, then the fixing position 62 can also be correspondingly established.

At the front side 88, which is an insertion side, the holder receptacle 84 has associated therewith an insertion ramp 96 (FIG. 13). The tab 86 of the suction bar 40 can be positioned in the opening 94 in a direction of insertion 98. The insertion ramp 96 has at least one wall 100 which is oriented at an incline to the direction of insertion 98 in order to facilitate insertion.

In the exemplary embodiment as depicted in FIG. 13, opposed walls 100 are provided, each of which is oriented at an incline to the direction of insertion 98.

By virtue of the insertion ramp 96, a form of insertion funnel for the tab 86 is formed at the holder receptacle 84.

The holder receptacle 84, when seen in a longitudinal direction 102 (cf. FIG. 10), which is a direction parallel to the direction of insertion 98, is placed in spaced relation with respect to the contact region 58 having the contact surface 64. A further support region to support the suction bar 40 in spaced relation to the contact surface 64 is thereby provided for the suction bar 40 in the fixing position 62 at the holder 38.

It is in particular provided that, when seen in a height direction 104 (cf. FIG. 10), the holder receptacle 84 is placed in spaced relation with respect to the contact region 58, and the contact surface 64 in particular (see FIGS. 10 and 13).

It is, in principle, also possible for the holder receptacle 84 to have, at the opening 94 thereof, a directly adjoining relationship with the contact surface 64 and, for example, for the contact region 58, at an inner side thereof where the contact surface 64 lies, to form the cover wall 92 c.

In particular, the further support provided to the suction bar 40 via the tab 86 within the holder receptacle 84 prevents the suction bar 40 from tilting at the holder 38 when in the fixing position 62.

The holder 38, and the holding part 56 in particular, are configured with at least approximate mirror symmetry about a central plane 106 (FIG. 4).

The holding part 56 of the holder 38 has a finger 108 at an outer end region of the contact region 58. The finger 108 laterally bounds the holding part 56.

At an end face 110, the finger 108 is formed in an arcuate shape, and, here, in a convexly arcuate shape. Adjoining the finger 108 in a direction towards the central housing box 66 is an indentation 112. The indentation 112 is rounded, formed with an arcuate configuration; it has a concave boundary.

The indentation 112 is bounded by a web 114, or transitions into said web. The end face 110 of the finger 108 and a corresponding end face of the web 114 are spaced from one another via the indentation 112, wherein a continuous transition is present via the concave boundary.

At a location lying next to the housing box 66, the contact region 58 has a region 116. Located between the region 116 and the web 114 is a further indentation 118. The further indentation 118 is, for example, cuboid-shaped with a rounded back side.

In particular, the further indentation 118 has a smaller width in a width direction 120 of the holding part 56 than the indentation 112.

Because the holding part 56 is configured to have mirror symmetry, in particular at the contact region 58 of the central plane 106, the aforementioned structure, including the elements of further indentation, web, indentation, finger, is duplicated.

This geometrical configuration of the holding part 56 conforms to the suction bar 40 in order to be able to fix same in the fixing position 62 and in order to be able to partially or fully release the suction bar 40 from its fixing position 62 at the holder 38 when an overload situation occurs.

The holding part 56 has formed at its contact region 58 and, relative to the fixing position 62, on a side thereof that faces towards the suction bar 40, at least one nose 122 (FIGS. 10, 12). In particular, two noses 122 are provided in a mirror-symmetrical arrangement about the central plane 106.

Furthermore, a nose 122 is arranged at the region 116 in particular.

The corresponding nose 122 serves to establish a form-locking connection, in particular in the fixing position 62 of the suction bar 40 at the holder 38. The suction bar 40 comprises corresponding counter elements, namely a first form-locking element 124 associated with a nose 122, wherein the associated nose 122 then forms a second form-locking element for a corresponding form-locking connection. This will be explained in more detail below.

As an example, a nose 122 is of wedge-shaped configuration. The corresponding nose 122 has a blocking region 126 a for the first form-locking element 124 and an inclined plane 126 b which adjoins the blocking region 126 a. In particular, the first form-locking element 124 can be overridden via the inclined plane 126 b. This is explained in more detail below.

In a wedge-shaped configuration, the blocking region 126 a is formed at the “steep” slope, while the inclined plane 126 b is formed at the “flat” slope.

A height of the nose 122 above the contact surface 64 (cf. FIG. 10, for example) increases along the inclined plane 126 b in a direction 128 towards the blocking region 126 a. Here, the direction 128 is perpendicular to the width direction 120, and is also parallel to the direction of insertion 98 in particular.

The suction bar 40 comprises a bar body 130. The bar body 130 extends between a first end face 132 and a second end face 134 along an axis of extent 136.

In an exemplary embodiment, the suction bar 40 has a curved configuration and the axis of extent 136 is correspondingly curved.

In particular, the suction bar 40 has an apex region 138 with respect to which, in the fixing position 62 and fitted to a cleaning machine 10, the suction bar 40 is curved in a convex shape when viewed in a direction from the front end 50 towards the rear end 48 of the cleaning machine 10, that is, it is curved in the direction towards the front end 50.

In an embodiment, provision is made for the suction bar 40 to have a length along the axis of extent 136 such that it projects beyond the chassis 12 on the left hand side and on the right hand side (cf. FIGS. 1 and 2).

It is in particular further provided for the suction bar 40 to not substantially project beyond the rear end 48 of the cleaning machine 10.

In particular, the suction bar 40, with its bar body 130, has at least approximate mirror symmetry about a central plane 140, wherein the central plane 140 lies centrally between the first end face 132 and the second end face 134.

Arranged at the bar body, in the region of the end faces 132, 134, is in each case a castor wheel element 142, or the castor wheel element 142 forms the end faces 132, 134 in each case.

The castor wheel element 142 comprises (at least) one castor wheel 144 which, in operation of the cleaning machine 10, can roll over the floor 36 being cleaned. This provides additional support for the suction bar 40.

Here, the corresponding castor wheels 144 of the castor wheel elements 142 are arranged such that they are outside of a cleaning liquid floor pattern. The castor wheels 144 point outwardly in a direction from the front end 50 to the rear end 48.

Furthermore, the castor wheel elements 142 are in each case provided at an end region thereof with a roller 146 which is for rolling along a wall surface. The rollers 146 provide a form of lateral stop bumpers.

In an embodiment, the castor wheel element 142 further comprises a hand grip, and comprises a hoop-type grip 148 in particular. The hoop-type grip 148 is positioned between castor wheels 144 and 146.

Contact elements 150 for contact against the floor 36 to be cleaned are arranged at the bar body 130 of the suction bar 40. In suction mode of operation of the cleaning machine 10, the contact elements 150 are supported on the floor 36 (FIG. 8). They define a plane of support 152 for the floor 36.

In particular, a first contact element 150 a (a first suction lip) is provided, which first contact element 150 a points outwardly (viewed in a direction from the front end 50 to the rear end 48).

In spaced relation to the first contact element 150 a is provided a second contact element 150 b (a second suction lip) which points towards the front end 50 when viewed in a direction from the rear end 48 to the front end 50 of the cleaning machine 10 (in the fixing position 62 of the suction bar 40).

Here, the second contact element 150 b faces towards the cleaning tool 28.

The contact element 150 b can be provided with recesses.

A suction space 154 is formed between the contact elements 150 a and 150 b. In suction mode of operation of the cleaning machine 10, the suction space 154 has applied thereto a suction flow which is provided by the suction unit device 42. Excess liquid can thereby be correspondingly taken up from the floor 36 by suction.

In an embodiment, a ledge 156 is arranged at the bar body 130. The ledge 156 is removable from the bar body 130. Fastening elements 158 are provided for connection. The fastening elements 158 are screws in particular.

In operation of the cleaning machine 10, the ledge 156 is fixedly connected to the bar body 130 via the fastening elements 158.

By releasing the ledge 156 from the bar body 130, the contact elements 150 can be replaced.

The port 82 for the suction conduit 80 is arranged on the central plane 140 of the suction bar 40. The port 82 conforms to the housing box 66. To this end, an elevation 160 is arranged at the bar body 130. The elevation 160 has an inclined surface 162. A port mouth 164 is positioned at the inclined surface 162. The port mouth 164 is operatively connected to the suction space 154 for fluid communication therewith.

In the fixing position 62, the housing box 66 is located above the elevation 160, wherein an operative connection and fluid communication is established between the suction conduit 80 and the port mouth 164.

In particular, the elevation 160 can, in a sense, be slid into the housing box 66 in the direction of insertion 98 (whereby the tab 86 is also simultaneously slid into the holder receptacle 84).

Here, the port 82 and the housing box 66 are in particular configured such that this process of inserting one within the other in the fixing position 62 automatically establishes an operative connection and fluid communication, and also fluid-tight communication as well. To this end, a corresponding seal is arranged in particular at the housing box 66 and/or at the port mouth 164, which seal provides a fluid-tight connection, and, here, provides automatic sealing in the fixing position 62 in particular.

The housing box 66 has a support surface 173 via which it can be supported on the support region 60 of the suction bar 40 when in the fixing position 62.

The tab 86 is arranged symmetrically with respect to the central plane 140 on a side of the bar body 130 that faces away from the first contact element 150 a. It is thus centrally arranged at the suction bar 40.

The tab 86 is formed as a hoop. It comprises a longitudinal web 166 that is in spaced relation to the bar body 130. The tab 86 is connected to the bar body 130 via spaced transverse webs 168 a, 168 b, which are in spaced relation to one another. A free space 170 is provided between the longitudinal web 166 and the transverse webs 168 a, 168 b.

The tab 86 is formed as a hand grip via which an operator can carry the suction bar 40. As mentioned, the tab 86 is formed as a hoop-type grip in particular.

In an exemplary embodiment, the support region 60 of the suction bar, which serves to have the contact region 58 of the holder 38 brought in contact thereagainst, is formed at the ledge 156. The support region 60 has a substantially planar contact surface 172 for the contact surface 64 of the holding part 56.

In an embodiment, the tab 86 is offset in height relative to the contact surface 172 in a direction towards the plane of support 152.

In an alternative embodiment, an upper side of the tab 86 is on the same plane as the contact surface 172.

The tab 86 extends beyond the bar body 130.

A fixing device 174 is provided for fixing the suction bar 40 at the holder 38 and for securing the fixing position 62 in place.

The fixing device 174 comprises a first clamping element 176 and a second clamping element 178 in spaced relation to the first clamping element. In particular, the first clamping element 176 and the second clamping element 178 are in a mirror symmetry arrangement about the central plane 140. The port 82 is located between the first clamping element 176 and the second clamping element 178 at the suction bar 40.

The first clamping element 176 and the second clamping element 178 are each formed as clamping levers, and are formed as eccentric levers in particular.

The first clamping element 176 and the second clamping element 178 each comprise a bearing element 180. The bearing element 180 is supported for displacement in a direction of displacement 182 on the suction bar 40, and is supported on the bar body 130 in particular.

The bearing element 180 has a first region 184 which projects upwardly beyond the support region 60 and, here, beyond the ledge 156.

The bearing element 180 has a second region 186 which passes through an opening 188 in the ledge 156.

The bearing element 180 further has a third region 190 which is positioned above the suction space 154.

Arranged at the first region 184 is a pivot element 194 which is supported for pivotal movement by a pivot bearing 192. A pivot axis 196 is oriented transversely and, in particular, perpendicularly to the direction of displacement 182.

The pivot element 194 has a clamping surface 198 which is a contact surface for the holding part 56 and, here, for the contact region 58 thereof that faces away from the contact surface 64. By way of the clamping surface 198, the holding part 56 of the holder 38, which is then in contact against the support region 60, can be clamped between the pivot element 194 and the support region 60.

The clamping surface 198 is in spaced relation to the pivot axis 196.

Arranged at the third region 190 of the bearing element 180 is an annular element 200. A spring device 202 is supported on the annular element 200. The spring device 202 is further supported on the bar body 130 at an inner side 204 thereof which is in opposing relation to the annular element 200.

In FIGS. 5 and 8, an open position of the clamping elements 176, 178 is shown. In FIGS. 3, 4, 6, 7, 9, 10, a fixing position is shown which corresponds to the fixing position 62 of the suction bar 40 at the holder 38.

In said fixing position which corresponds to the fixing position 62, the pivot element 194, via the clamping surface 198 surface thereof, urges the contact region 58 of the holding part 56 of the holder 38 against the support region 60 of the suction bar 40, thereby clamping the suction bar 40 against the holder 38 in a force-locking manner. A force-locking connection is established.

Here, the spring device 202 is arranged and configured such that it tends to urge the bearing element 180 away from the inner side 204 to thereby urge the clamping surface 198 in a direction against the contact surface 172 at the suction bar 40. This in turn causes the holding part 56 to be clamped between the clamping surfaces 198 of the clamping elements 176, 178 and the bar body 130.

The spring device 202 is configured and arranged such that a spring force 206 (cf. FIG. 9) acts in a direction away from the inner side 204 and towards the plane of support 152.

By pivoting the pivot element 194 about the pivot axis 196 from the open position (FIG. 8) to the closed position (FIG. 9), the bearing element 180 is displaced upwardly in the displacement direction 182, i.e., away from the plane of support 152. The spring device 202 is thereby tensioned. When the clamping surface 198 is in contact against the contact region 58 of the holder 38, then on the one hand such closed position is fixed in place by virtue of the corresponding configuration of the clamping elements 176, 178. On the other hand, the spring force 206 provides for the holder 38 to be clamped against the suction bar (and the clamping elements 176, 178 thereof). The corresponding fixing in place via the clamping elements 176, 178 is force-locking in nature.

The noses 122 as the second form-locking elements have associated therewith the first form-locking elements 124 at the suction bar 40. The corresponding second form-locking elements 124, which are arranged symmetrically with respect to the central plane 140 and are aligned with the noses 122, are formed as elevations extending from the contact surface 172. They permit a form-locking connection to be achieved in addition to the force-locking connection that is achieved with the clamping elements 176, 178.

When the form-locking connection is established, the blocking region 126 a of a nose 122 is in contact against the associated first form-locking element 124. Movement of the suction bar 40 in a direction 208 is thereby blocked. The direction 208 is a direction opposite to the direction 128.

An overload protection device is associated with the suction bar 40. The overload protection device provides for the suction bar 40 to be partially or fully releasable from the holder 38 when an overload situation is encountered.

By virtue of the force-locking connection of the suction bar 40 with the holder 38, a release is possible, i.e., the force-locking connection can be released if a corresponding acting force exceeds the force of the force lock. In particular, said force of the force lock can be adjusted by a corresponding configuration and arrangement of the spring device 202.

By the provision of the form-locking connection using the form-locking elements 122, 124, an additional connection is achieved, wherein the form locking relation can likewise be released when an overload situation is encountered. This is indicated by the intermediate position shown in FIG. 12. Here, the first form-locking element 124 can be overridden by the inclined plane 126 b of the second form-locking element 122 in order to enable a corresponding release and thereby to release the contact therebetween with respect to the direction 208.

In particular, the first form-locking element 124 has an elevation height above the contact surface 172, and the second form-locking element 122 correspondingly conforms thereto so that in an expected overload situation said overriding of the first form-locking element 124 by the second form-locking element 122 is possible. To this end, for example, the first form-locking element 124 has a height above the contact surface 172 which is no more than 2 cm, and is no more than 1 cm in particular. The nose 122 correspondingly conforms therewith. In an embodiment, the elevation height is about 0.9 cm.

A first wall 210 and a second wall 212 are arranged symmetrically with respect to the central plane 140 at the support region 60 of the suction bar 40, and at the ledge 156 in particular. The first wall 210 and the second wall 212 are each formed with an arcuate configuration. They are open upwardly and in a direction 214. The direction 214 points towards the holder 38 when in the fixing position 62.

The walls 210, 212 are closed on a side thereof facing away from the upper side, and are bounded by the support region 60 in particular.

The walls 210, 212 define a receptacle 216 for the fingers 108 of the holding part 56 in each case.

The corresponding finger 108 is extended into in the receptacle 216 when in the fixing position 62.

A fastening element 158 is positioned in the indentation 112 when in the fixing position 62 (cf. FIG. 7).

A corresponding bearing element 180 of the clamping elements 176 and 178 is located in the further indentation 118. The respective web 114 is then positioned between the corresponding fastening element 158 and the corresponding bearing element 180.

A rotational bearing is formed by the finger 108 and the respective wall 210 and 212 associated therewith. A first rotational bearing 218 (including wall 210) and a second rotational bearing 220 are provided. The first rotational bearing 218 and the second rotational bearing 220 are symmetrical about the central plane 140, relative to the fixing position 62.

Under conditions of normal operation, the rotational bearings 218, 220 have no function. They become operative in an overload situation.

In an overload situation, the suction bar 40 can rotate at the holder 38, and, here, while still remaining with the holder, can rotate on the first rotational bearing 218 or on the second rotational bearing 220, depending on the particular overload situation. A force can thereby be avoided in order to achieve overload protection.

The first rotational bearing 218 has associated therewith a first axis of rotation 222. The second rotational bearing 220 has associated therewith a second axis of rotation 224. The first axis of rotation 222 and/or the second axis of rotation 224 are oriented transversely, and in particular perpendicularly, to the contact surface 64 and the contact surface 172.

They are oriented transversely, and in particular perpendicularly, to the plane of support 152.

They are oriented transversely, and in particular perpendicularly, to the wheel axis 32.

They are oriented transversely, and in particular perpendicularly, to the axis of extent 136.

They extend at least near parallel (with a deviation of no more than 10°) to the central planes 106 and 140.

The rotational bearings 218, 220 are in spaced relation to the port 82 and the housing box 66.

The cleaning machine 10 works as follows:

In a cleaning mode of operation of the cleaning machine 10, which is a floor cleaning machine, the suction bar 40 is fixed in place at the holder 38 when in the fixing position 62.

Cleaning liquid is applied to the floor 36 to be cleaned via the corresponding application device 34. The one or more cleaning tools 98 perform a mechanical cleaning action, wherein the cleaning liquid provides improved release of dirt on the floor 36 being cleaned.

The cleaning machine 10 is formed of self-propelled configuration and traverses a corresponding cleaning area. Excess liquid is sucked up via the suction bar 40. The suction unit device 42 in suction mode of operation generates a suction flow which is applied to the suction space 154. Via corresponding recesses 226 provided in the second contact element 150 b, liquid can enter the suction space 154 whence it can be drawn off.

In cleaning mode of operation, the contact elements are supported on the floor 36 against their plane of support 152.

Liquid being drawn in is received in the dirty fluid tank 44.

The suction bar 40 is releasable from the holder 38.

In order to fix a suction bar 40 in place on the cleaning machine 10 after it has been removed from the latter, the clamping elements 176, 178 are opened (FIGS. 5, 8). When in this open position, the corresponding pivot elements 194 are pivoted such that the respective first region 184 of the bearing elements 180 is in contact against the support region 60.

The suction bar 40 is then inserted into the holder 38. To this end, the tab 86 is brought into the holder receptacle 84. Automatic positioning is thereby achieved.

The contact region 58 is in contact against the support region 60. The corresponding fingers 108 are positioned in their respective receptacles 216. The corresponding fastening elements 158 are located in the indentations 112.

The bearing elements 180 are positioned in the respective further indentation 118.

The pivot elements 194 are then closed by a pivoting movement in a pivoting direction 228 (FIG. 8). This causes the corresponding bearing elements 180 to be displaced. The clamping surfaces 198 are urged against the holder 38. The corresponding spring devices 202 are tensioned. The contact region 58 is clamped against the suction bar 40 via the clamping elements 176, 178.

The spring device 202 is tensioned.

A force-locking connection is thereby produced.

In addition, this causes the noses 122 to be placed in contact against the first form-locking elements 124, and a form lock is achieved with respect to the direction 208. Here, said form lock occurs at at least two locations symmetric with respect to the central plane 140.

By virtue of such positioning of the suction bar 40 at the holder 38, the housing box 66 is also brought over the port 82 and this then provides for the suction conduit 80 to be in operative connection and fluid communication with the suction bar 40, i.e., for it to be in operative connection and fluid communication with the suction space 154.

The cleaning machine 10 is now ready for suction mode of operation.

By the provision of the tab 86 which is also formed as a hand grip, further support is provided to the suction bar in addition to the support thereof at the holder 38, and, here, at the contact region 58. In particular, such further support prevents the suction bar 40 from tilting relative to the holder 38.

In the event that the suction bar 40 in cleaning mode collides against an obstacle and, in particular, if the corresponding applied force is large enough, the suction bar 40, supported on the floor 36, can rotate at the holder 38 via one of the rotational bearings 218, 220 (depending on the applied force) and, thus, avoid the force application. This provides a way of “compensating” for a corresponding overload situation, thereby accommodating the overload on the suction bar 40 or the cleaning machine 10. The suction bar 40 can avoid the overload situation. Damage is thereby avoided. The suction bar 40 can then fall from the holder 38.

In a corresponding overload situation, it is also possible for the suction bar 40 to release from the holder 38 and hence fall from the cleaning machine 10 without prior rotation.

FIG. 12 shows a corresponding intermediate situation in comparison to FIG. 10. In such an overload event, the force exerted on the suction bar 40 and/or the on holder 38 is such that, correspondingly, a nose 122 at the holder 38 can move over the first form-locking element 124 at the suction bar 40 and override it. The form-locking connection is thereby released and the suction bar 40 can move relative to the holder 38 in direction 208. The previously present contact (FIG. 10) is released, and the suction bar 40 is thereby allowed to fall off.

The walls 210, 212 have a height H (cf. FIG. 5) above the contact surface 172 such that a corresponding release is possible. Since the corresponding receptacles 216 are open upwardly, a finger 108 can be brought out of the associated receptacle 216 in an upward direction.

Furthermore, the suction bar 40 can be released at the corresponding first rotational bearing 218, 220 by a forward movement relative to the holder 38.

In particular, a height H of the corresponding wall 210 or 212 is no more than 5 cm, and in particular no more than 4 cm, and in particular no more than 2 cm. In a concrete embodiment, the height is about 1.1 cm.

The wall 210 or 212, on at least a side that faces towards the receptacle 216, is formed with an arcuate configuration, and is formed with a convex configuration in particular. It is thereby possible for the respective finger 108, which is formed with concave configuration, to effect a rolling motion for the rotary motion capability.

Machine-side attachment of the suction bar 40 to the cleaning machine 10 is realized via the holder 38. Such attachment is not rigid but flexible. A combination of force-locking connection and form-locking connection is provided. A defined position of the suction bar 40 (the fixing position 62) can thereby be achieved during “normal” cleaning operation of the cleaning machine 10. When the loading imposed on said attachment exceeds a certain threshold value, the suction bar 40 can be partially or fully released.

Damage to objects and to the cleaning machine 10 can thereby be prevented via the corresponding overload protection device.

If, as an example, the suction bar 40 snags onto an object during a cleaning run, it can experience a force acting thereon that will cause the suction bar 40 to rotate at the holder 38 via the first rotational bearing 218 or 220. If one side of the suction bar 40 snags, the latter rotates in a controlled manner about a defined center of rotation which is predetermined by the first rotational bearing 218 or the second rotational bearing 220.

In certain overload situations, the suction bar 40 can also release from the corresponding attachment without prior rotation.

Here, the suction conduit 80 remains with the machine. A releasable connection is provided via the port 82 and the housing box 66, which releasable connection allows the suction bar 40 to partially or fully release from the holder 38.

In particular, a sensor device is provided which detects partial or complete release of the suction bar 40 from the holder 38. A corresponding signal is then provided to an operator so that the operator may again adjust the fixing position 62.

By virtue of the tab 86 and the associated holder receptacle 84, the suction bar 40 is prevented from tilting (angular shift) at the holder 38.

Via the clamping elements 176, 178, a simple way is provided for an operator to mount or dismount the suction bar 40 to or from the holder 38. Only a small application of hand force is required to accomplish this purpose. In particular, an overload force can be decoupled from a force required for mounting or dismounting.

Corresponding overload forces for overload situations can be adjusted by adapting the parameters relevant to the force-locking connection and the form-locking connection.

In particular, the cleaning machine 10 is formed of self-propelled configuration. In the exemplary example illustrated, it is configured as a ride-on machine. It is also possible for the cleaning machine 10 to be configured, for example, as a stand-on machine or as a walk-behind machine.

In an exemplary embodiment, the cleaning machine 10 comprises a checking device 230 to check for blockage formed at a suction path 232. It is thereby possible to recognize whether a blockage occurs at some location within the suction path 232, such as for example within the suction conduit 80, requiring intervention on the part of the operator.

Correspondingly, the checking device 230 provides an indication to the operator to show the presence or likely presence of a blockage condition.

The checking device 230 comprises (at least) one pressure sensor 234. In an exemplary embodiment, a further pressure sensor 236 is provided which is arranged at the fan of the suction unit device 42.

As an example, a differential pressure measurement is performed, wherein pressure values are measured via the pressure sensor 234 and the further pressure sensor 236.

It is, in principle, also possible for only one pressure sensor, such as the pressure sensor 234, to be provided and for the necessary data to be then taken from a known characteristic curve family.

If, then, for example, the deviation between a pressure measurement value at the pressure sensor 234 and a fan characteristic plot is greater than specified, it can be assumed that a blockage is present in the suction path 232.

It is useful for a pressure measurement to be taken in the suction space 154.

Because the suction bar 40 is releasable from the holder 38 in an overload event, it is further advantageous for the pressure sensor 234 to be arranged in the cleaning machine 10 or at the holder 38, and for it not to be arranged in the suction bar 40. In an exemplary embodiment, a pressure conduit 238 is provided which is operatively connected to the suction space 154 for fluid communication therewith. The pressure conduit 238 leads to the pressure sensor 234 outside of the suction space 154, and outside of the suction bar 40 in particular. Via the pressure conduit 238, the pressure in the suction space 154 can be determined at a distance from the suction space 154.

In an exemplary embodiment, the pressure conduit 238 is connected to the suction conduit 80.

In particular, then, a corresponding port for the pressure conduit 238 is arranged at the port 82. Said port for the pressure conduit is indicated in FIG. 5 by the reference numeral 240.

In particular, the checking device 230 can in principle also be utilized to detect when the suction bar 40 has fully released from the holder 38.

For example, the pressure in the suction space 154 is then measured via the pressure sensor 234 at a distance from the suction space 154. This is compared, via the checking device 230, with threshold values derived, for example, from a fan characteristic plot, and the operator is alerted to error conditions when a threshold value is exceeded or not reached.

For example, corresponding pressure values of the fan can be calculated from the fan characteristic plot at all operating conditions. This provides a way of conducting a differential pressure measurement without use of a second pressure sensor, although, as mentioned already, a further pressure sensor 236 can be used.

In addition, this provides a way of recognizing, for example, whether the first contact elements 150 a, 150 b (suction lips) have become worn, or of detecting the nature of ground of the floor 36 being cleaned. For example, it is possible to provide pressure monitoring over the life of the contact elements 150, including corresponding evaluation of the pressure increase or of the pressure course, averaged over different floor surfaces for example.

As mentioned above, the checking device 230 can also be used to detect a suction bar 40 release event.

The pressure conduit 238 remains with the machine when the suction bar 40 is released.

Another exemplary embodiment (FIGS. 15 to 17) comprises a holder 250. The holder 250 comprises a fastening part 252 and an intermediate part 254. The fastening part 252 is fixed at the chassis 12 of the corresponding floor cleaning machine. It is mounted to the chassis 12 in a fixed manner or with capability for height adjustment.

The intermediate part 254 is oriented at an incline to the fastening part 252.

When in a mounted condition, the intermediate part 254 has an underside 256 facing towards a floor 36 to be cleaned and an upper side 258 opposite thereto.

The upper side 258 is in spaced relation to the chassis 12, and is for example in at least near-parallel spaced relation thereto.

Articulated to the intermediate part 254 via a pivot joint 260 is a holding part 262. The holding part 262 serves to directly hold a suction bar 264.

In particular, the holding part 262 comprises a contact region 266 for the suction bar 264, which contact region 266 corresponds to the contact region 58 as has been described above for the case of the holder 38.

In principle, the suction bar 264 and the suction bar 40 can have substantially identical configuration.

Here, it is possible for the fixing of the suction bar 264 on the holding part 262 to be carried out substantially the same way as has been described above for the case of holder 38 and suction bar 40. In principle, a corresponding overload protection device can also be provided, as described before.

Furthermore, it is in principle possible for the overload protection device to be omitted or configured differently.

The holding part 262 is articulated to the intermediate part 254 for pivotal movement with respect thereto about a pivot axis 268 via the pivot joint 260.

The intermediate part 254 forms a first part 254 of the holder 250, and the holding part 262 forms a second part 262 of the holder 250, wherein the second part 262 is pivotally articulated to the first part 254 via the pivot joint 260.

The pivot axis 268 is oriented such that it is at least approximately parallel to a plane of support of the suction bar 264 on a floor 36 to be cleaned.

The pivot axis 268 is oriented at least approximately parallel to the wheel axis 32.

Furthermore, the pivot axis 268 is oriented transversely and, in particular, perpendicular to the direction of forward travel 16.

The pivot joint 260 is formed at the holder 250. In an embodiment, the pivot joint 260 comprises a pin 270 having a collar 272. The pin 270 is located in opposing receptacles 274 a, 274 b in rotationally fixed relation thereto. The receptacles 274 a, 274 b, which are of loop-like configuration, are themselves located at the holding part 262.

Located between the receptacles 274 a, 274 b, on the pin 270, rotatable about the pivot axis 268, is a sleeve 276. The sleeve 276 is connected to the intermediate part 254 in rotationally fixed relation thereto. As a result, the intermediate part 254 is rotatable relative to the pin 270 via the sleeve 276.

Furthermore, it is in principle possible for the pin 270 to be connected to the intermediate part 254 in rotationally fixed relation thereto and, correspondingly, for the capability for rotation to be achieved via corresponding rotatable mounting of the pin 270 at corresponding receptacles 274 a, 274 b.

The receptacles 274 a, 274 b at the holding part 262 are in spaced relation to the contact region 266 for the suction bar 264.

A locking device 278 is provided for adjusting and locking in place a defined pivot position of the holding part 262 relative to the intermediate part 254 (and thereby of the suction bar 264 relative to the intermediate part 254). The locking device 278 connects, in spaced relation to the pivot joint 260, the holding part 262 to the intermediate part 254 and hence the second part 262 of the holder 250 to the first part 254 of the holder 250.

In an exemplary embodiment, the locking device 278 comprises a pin element 280 which is formed as an adjusting screw.

Arranged between the intermediate part 254 and the holding part 262 is a compression spring device 282 (cf. FIG. 16) which comprises one or more compression springs. The compression spring device 282 is supported both on the intermediate part 254, and here on the underside 256 thereof, and on the holding part 262.

The compression spring device 282 seeks to rotate the holding part 262 away from the intermediate part 254 in a direction 284 (FIG. 16).

A counter nut 286 is arranged at the pin element 280 via threads. The counter nut 286 is located at or above the upper side 258 of the intermediate part 254.

Via a counter element 288 which is arranged at the pin element 280 and which acts upon the holding part 262, an adjusted defined pivot position at the pivot joint 260 can then be prevented from being released.

In an embodiment, the counter element 288 has one or more spherical washers 290 associated therewith, which spherical washers 290 can compensate for angular differences resulting from adjustment of the pin element 280.

The pin element 280 comprises an engagement region 292 for a tool via which it is possible to rotate the pin element 280 for adjusting a corresponding pivot position and locking the pivot position. The engagement region 292 is located above the upper side 258 of the intermediate part 254, and, here, in spaced relation to the chassis 12.

Adjusting a height position of the pin element 280 at the intermediate part 254 adjusts an angular position of the holding part 262 at the intermediate part 254. An angular position of the suction bar 264 fixed on the holding part 262 is thereby adjusted relative to the intermediate part 254 or the chassis 12.

By way of example, the corresponding angular position can be adjusted when the holder 250 is being mounted or when a servicing operation is performed. In principle, it can also be adjusted by an operator.

For an optimal cleaning result to be achieved, the suction bar 264 need be oriented at the “appropriate angle” relative to the surface 36 being cleaned. Because of production tolerances, forces created during operation and also, for example, because of different requirements depending on the particular type of floor, a specific angular adjustment can be advantageous. As an example, under operating conditions, the suction bar 264 sucks down on the floor surface and tilts somewhat in the direction of forward travel 16. The adjustability of the angular position of the suction bar 264 relative to the chassis 12 via adjustment of the pivot position of the holding part 262 relative to the intermediate part 254 achieves appropriate adjustment to achieve an optimal cleaning result.

In particular, the pin element 280 (the locking device 278) is arranged between the fastening part 252 and the suction bar 264 when the suction bar 264 is arranged at the holder 250.

As mentioned above, it is possible for the holder 250 and the suction bar 264 to have associated therewith an overload protection device which is configured as has been described above, or to have a differently configured overload protection device, or to be devoid of such overload protection device.

In particular, the holder 250 and the suction bar 264 are combined with the overload protection device in accordance with the invention.

The solution in accordance with the invention with respect to the fixing device and the overload protection device can be used on an operator-controlled floor cleaning machine (for example, on a ride-on machine, a stand-on machine or a walk-behind machine). It can also find use in a cleaning robot which is in particular self-propelled and self-steering. In the same way, the solution with respect to the adjustment of an angle of inclination of the suction bar via a corresponding pivot joint can be used on an operator-controlled floor cleaning machine or on a robotic cleaner.

LIST OF REFERENCE CHARACTERS

-   10 cleaning machine -   12 chassis -   14 rear wheel device -   16 direction of forward travel -   18 left rear wheel -   20 right rear wheel -   22 front wheel -   24 steering wheel -   26 driver's seat -   28 cleaning tool -   30 axis of rotation -   32 wheel axis -   34 application device -   36 floor to be cleaned -   38 holder -   40 suction bar -   42 suction unit device -   44 dirty fluid tank -   46 width direction -   48 rear end -   50 front end -   52 fastening part -   54 intermediate part -   56 holding part -   58 contact region -   60 support region -   62 fixing position -   64 contact surface -   66 housing box -   68 front side -   70 side wall -   72 lid -   74 acute angle -   76 interior space -   78 connecting piece -   80 suction conduit -   82 port -   84 holder receptacle -   86 tab -   88 front side -   90 wall -   92 a rear wall -   92 b bottom wall -   92 c cover wall -   94 opening -   96 insertion ramp -   98 direction of insertion -   100 wall -   102 longitudinal direction -   104 height direction -   106 central plane -   108 finger -   110 end face -   112 indentation -   114 web -   116 region -   118 further indentation -   120 width direction -   122 nose, second form-locking element -   124 first form-locking element -   126 a blocking region -   126 b inclined plane -   128 direction -   130 bar body -   132 first end face -   134 second end face -   136 axis of extent -   138 apex region -   140 central plane -   142 castor wheel element -   144 castor wheel -   146 roller -   148 hand grip -   150 contact elements -   150 a first contact element -   150 b second contact element -   152 plane of support -   154 suction space -   156 ledge -   158 fastening element -   160 elevation -   162 inclined surface -   164 port mouth -   166 longitudinal web -   168 a transverse web -   168 b transverse web -   170 free space -   172 contact surface -   173 support surface -   174 fixing device -   176 first clamping element -   178 second clamping element -   180 bearing element -   182 direction of displacement -   184 first region -   186 second region -   188 opening -   190 third region -   192 pivot bearing -   194 pivot element -   196 pivot axis -   198 clamping surface -   200 annular element -   202 spring device -   204 inner side -   206 spring force -   208 direction -   210 first wall -   212 second wall -   214 direction -   216 receptacle -   218 first rotational bearing -   220 second rotational bearing -   222 first axis of rotation -   224 second axis of rotation -   226 recess -   228 pivoting direction -   230 checking device -   232 suction path -   234 pressure sensor -   236 further pressure sensor -   238 pressure conduit -   240 port for pressure conduit -   250 holder -   252 fastening part -   254 intermediate part (first part) -   256 underside -   258 upper side -   260 pivot joint -   262 holding part (second part) -   264 suction bar -   266 contact region -   268 pivot axis -   270 pin -   272 collar -   274 a, 274 b receptacle -   276 sleeve -   278 locking device -   280 pin element -   282 compression spring device -   284 direction -   286 counter nut -   288 counter element -   290 spherical washer -   292 engagement region 

1. Floor cleaning machine, comprising: a suction unit device; a suction bar which is operatively connectable, or operatively connected, to the suction unit device for fluid communication therewith; a holder which releasably holds the suction bar; a fixing device for releasably fixing the suction bar at the holder; and an overload protection device which is associated with the suction bar; wherein the overload protection device comprises at least one rotational bearing by way of which the suction bar is rotatable at the holder relative to the holder when an overload situation occurs.
 2. Floor cleaning machine in accordance with claim 1, wherein the at least one rotational bearing has an axis of rotation with at least one of the following: the axis of rotation is transverse to a plane of support of the suction bar on a floor to be cleaned; the axis of rotation is transverse to a wheel axis of the floor cleaning machine; the axis of rotation is in spaced relation to a central plane of the suction bar, which central plane lies between a first end face and a second end face of the suction bar, relative to a fixing position of the suction bar at the holder; the axis of rotation is oriented at least approximately parallel to a central plane which lies between a first end face and a second end face of the suction bar, relative to a fixing position of the suction bar at the holder.
 3. Floor cleaning machine in accordance with claim 2, wherein the at least one rotational bearing, relative to a fixing position of the suction bar at the holder, is at least one of (i) in spaced relation to a port for a suction conduit that is arranged at the suction bar, and (ii) in spaced relation to a central plane of the suction bar which lies between a first end face and a second end face of the suction bar.
 4. Floor cleaning machine in accordance with claim 1, wherein at least a first rotational bearing and a second rotational bearing are provided, which second rotational bearing is in spaced relation to the first rotational bearing, with at least one of the following: a first axis of rotation of the first rotational bearing and a second axis of rotation of the second rotational bearing are at least approximately parallel to one another; a central plane of the suction bar which lies between a first end face and a second end face of the suction bar, lies between the first rotational bearing and the second rotational bearing, relative to a fixing position of the suction bar at the holder; the first rotational bearing and the second rotational bearing are in a mirror-symmetrical arrangement about a central plane which lies between a first end face end and a second end face end of the suction bar; a port for a suction conduit at the suction bar is located between the first rotational bearing and the second rotational bearing, relative to a fixing position of the suction bar at the holder.
 5. Floor cleaning machine in accordance with claim 1, wherein the suction bar comprises a support region for the holder and the holder comprises a contact region for the support region of the suction bar.
 6. Floor cleaning machine in accordance with claim 5, wherein the support region has a planar contact surface.
 7. Floor cleaning machine in accordance with claim 5, wherein the at least one rotational bearing comprises a wall which is arranged at the support region of the suction bar, wherein the wall defines a receptacle, and the at least one rotational bearing comprises a counter element which is arranged at the contact region of the holder, wherein, in a fixing position of the suction bar at the holder, the counter element is positioned in the receptacle.
 8. Floor cleaning machine in accordance with claim 7, wherein at least one of the following is provided: the receptacle is closed towards the support region of the suction bar; the receptacle is open in a direction away from the support region; the receptacle is bounded by the wall in a direction away from the holder with respect to a fixing position of the suction bar at the holder; the receptacle is open towards the holder with respect to a fixing position of the suction bar at the holder; the wall has an arcuate shape; the wall extends in an angular range of at most 180°; the wall has a height (H) of no more than 5 cm.
 9. Floor cleaning machine in accordance with claim 7, wherein at least one of the following is provided: the counter element has an arcuate shape on an end face that faces towards the wall; the counter element is formed as a finger; the counter element is of planar configuration on an underside thereof facing towards the support region of the suction bar; the counter element is of planar configuration on an upper side thereof facing away from the underside; a height of the counter element between an upper side and an underside is no more than 2 cm.
 10. Floor cleaning machine in accordance with claim 7, wherein the counter element bounds an indentation at the holder, with at least one of the following: a fastening element of the suction bar is positioned in the indentation when the suction bar is in a fixing position at the holder; the indentation has an arcuate boundary; the indentation is bounded by a web on a side thereof facing away from the counter element.
 11. Floor cleaning machine in accordance with claim 1, wherein at least one tab is arranged at the suction bar for connection to the holder.
 12. Floor cleaning machine in accordance with claim 1, wherein at least one tab is arranged at the suction bar for connection to the holder, and wherein the at least one tab is formed as a hand grip for holding the suction bar.
 13. Floor cleaning machine in accordance with claim 11, wherein the at least one tab is formed as a hoop.
 14. Floor cleaning machine in accordance with claim 11, wherein the at least one tab is centrally arranged with respect to outer end faces of the suction bar.
 15. Floor cleaning machine in accordance with claim 11, wherein the holder comprises a holder receptacle for the at least one tab, wherein the at least one holder receptacle is configured for providing support to the tab.
 16. Floor cleaning machine in accordance with claim 15, wherein at least one of the following is provided: the holder receptacle is configured for providing support to the at least one tab downwardly towards a floor to be cleaned; the holder receptacle is configured for providing support to the at least one tab upwardly in a direction away from a floor to be cleaned; the holder receptacle is open on an insertion side; the holder receptacle has associated therewith an insertion ramp on an insertion side.
 17. Floor cleaning machine in accordance with claim 15, wherein the holder comprises a contact region and the suction bar comprises a support region for the contact region, wherein the contact region is in spaced relation to the holder receptacle for the at least one tab.
 18. Floor cleaning machine in accordance with claim 1, wherein a housing box is arranged at the holder, to which housing box is connected a suction conduit, and wherein the housing box, in a fixing position of the suction bar at the holder, is positioned over a port for a suction conduit at the suction bar.
 19. Floor cleaning machine in accordance with claim 18, wherein at least one of the following is provided: the housing box comprises a support surface for the suction bar; the port for a suction conduit at the suction bar has an inclined surface at which a port mouth is positioned; the housing box is in spaced relation to at least one engagement region of the fixing device; a holder receptacle for at least one tab of the suction bar for fixing the suction bar at the holder is arranged in the region of the housing box; the holder receptacle is spaced in height from the housing box; in a fixing position of the suction bar at the holder, operative connection and fluid communication between a suction conduit and a port for a suction conduit at the suction bar is established; the holder receptacle conforms to the at least one tab such that, when the suction bar is fixed at the holder with the at least one tab received in the holder receptacle, the holder is automatically positioned relative to the suction bar such that the at least one rotational bearing is formed.
 20. Floor cleaning machine in accordance with claim 1, wherein the fixing device is configured such that in a fixing position of the suction bar at the holder, a force-locking connection exists between the holder and the suction bar.
 21. Floor cleaning machine in accordance with claim 1, wherein the fixing device is configured such that in a fixing position of the suction bar at the holder, a form-locking connection exists between the holder and the suction bar.
 22. Floor cleaning machine in accordance with claim 1, wherein the fixing device is configured such that in a fixing position of the suction bar at the holder, a form-locking connection exists between the holder and the suction bar, and exists in addition to a force-locking connection.
 23. Floor cleaning machine in accordance with claim 20, wherein the fixing device comprises at least one clamping element which is arranged at the suction bar and via which the holder is clampable against the suction bar.
 24. Floor cleaning machine in accordance with claim 23, wherein the suction bar comprises a support region for the holder and the holder comprises a contact region for the support region of the suction bar, and wherein the at least one clamping element is configured such that the contact region of the holder is clampable between the support region and the at least one clamping element.
 25. Floor cleaning machine in accordance with claim 23, wherein at least one of the following is provided: the at least one clamping element is formed as a clamping lever; the at least one clamping element comprises a pivot element which has a clamping surface and which is pivotably mounted on a bearing element; a bearing element of the at least one clamping element is mounted for displacement on the suction bar; a direction of displacement of the bearing element is oriented transversely to a pivot axis of the pivot element; the bearing element is supported on the suction bar via a spring device; a spring force of the spring device in a clamping position of the at least one clamping element exerts a clamping force for fixing the holder and the suction bar together in a form-locking manner; at least one of the direction of displacement of the bearing element and a direction of force of the spring device is oriented at least approximately parallel to an axis of rotation of the at least one rotational bearing.
 26. Floor cleaning machine in accordance with claim 23, wherein at least a first clamping element and a second clamping element are provided, the second clamping element being in spaced relation to the first clamping element, with at least one of the following: the first clamping element and the second clamping element are arranged outside of a central plane of the suction bar which lies between a first end face and a second end face of the suction bar; the first clamping element and the second clamping element have mirror symmetry about a central plane of the suction bar which lies between a first end face and a second end face; a port for a suction conduit is positioned between the first clamping element and the second clamping element; the first clamping element and the second clamping element are located between a first rotational bearing and a second rotational bearing.
 27. Floor cleaning machine in accordance with claim 21, wherein the fixing device comprises at least one first form-locking element which is arranged at the suction bar, and at least one second form-locking element which corresponds to the first form-locking element and is arranged at the holder.
 28. Floor cleaning machine in accordance with claim 27, wherein the at least one first form-locking element and the at least second form-locking element are arranged and configured such that, in a fixing position of the suction bar at the holder, when a force-locking connection is established between the suction bar and the holder, a form-locking connection with the at least one first form-locking element and the at least one second form-locking element is also established.
 29. Floor cleaning machine in accordance with claim 28, wherein the at least one first form-locking element is arranged at a support region of the suction bar for the holder.
 30. Floor cleaning machine in accordance with claim 27, wherein the at least one first form-locking element and the at least one second form-locking element are configured to conform to one another such that, in a fixing position of the suction bar at the holder, a movement of the suction bar away from the holder in a blocking direction is blocked by a form lock, with at least one of the following: the blocking direction is at least approximately parallel to a plane of support of the suction bar on a floor to be cleaned; the blocking direction is at least approximately parallel to a direction of insertion of at least one tab of the suction bar into a holder receptacle of the holder; the blocking direction is transverse to an axis of rotation of the at least one rotational bearing; the blocking direction is at least approximately parallel to a chassis axis of the cleaning machine; the blocking direction is at least approximately parallel to a support region of the suction bar for the holder; the blocking direction is transverse to a wheel axis; the blocking direction is a unidirectional direction away from the holder.
 31. Floor cleaning machine in accordance with claim 27, wherein, when a sufficiently large force is applied to the suction bar, the at least one second form-locking element is releasable from the at least one first form-locking element.
 32. Floor cleaning machine in accordance with claim 27, wherein the at least one first form-locking element is formed by an elevation at the suction bar and wherein the at least one second form-locking element is a nose at the holder.
 33. Floor cleaning machine in accordance with claim 27, wherein the at least one second form-locking element has a blocking region for the at least one first form-locking element, with which blocking region the second form-locking element is in contact against the first form-locking element when in a form-locking connection, and wherein the at least one second form-locking element has an inclined plane for overriding the at least one first form-locking element.
 34. Floor cleaning machine in accordance with claim 1, wherein in an overload event, the suction bar at least one of (i) rotates relative to the holder and (ii) falls off the holder.
 35. Floor cleaning machine in accordance with claim 1, wherein a checking device is provided to check for blockage at a suction path.
 36. Floor cleaning machine in accordance with claim 35, wherein at least one pressure sensor is provided which is arranged at the suction path.
 37. Floor cleaning machine in accordance with claim 36, wherein the pressure sensor is arranged at a pressure conduit which is connectable, or is connected, to the suction bar.
 38. Floor cleaning machine in accordance with claim 37, wherein a port for a suction conduit at the suction bar comprises a port for the pressure conduit.
 39. Floor cleaning machine in accordance with claim 37, wherein the pressure conduit is connected to a suction conduit.
 40. Floor cleaning machine, comprising: a chassis; a suction unit device; a suction bar which is operatively connectable, or operatively connected, to the suction unit device for fluid communication therewith; and a holder which is connected to the chassis and which holds the suction bar; wherein the holder has associated therewith a pivot joint via which the suction bar is pivotable relative to the chassis; and wherein a locking device is provided via which an adjusted pivot position of the suction bar relative to the chassis is lockable in place.
 41. Floor cleaning machine in accordance with claim 40, wherein at least one of the following is provided: a pivot axis of the pivot joint is oriented at least approximately parallel to a plane of support of the suction bar on a floor to be cleaned; the pivot axis is oriented at least approximately parallel to a wheel axis; the pivot axis is oriented transversely to a direction of forward travel.
 42. Floor cleaning machine in accordance with claim 40, wherein the holder is formed of multi-part configuration and the pivot joint is integrated in the holder.
 43. Floor cleaning machine in accordance with claim 40, wherein the holder comprises a first part and a second part, wherein the second part comprises a contact region for the suction bar, the second part is connected to the first part via the pivot joint, and the second part is lockably pivotable relative to the first part.
 44. Floor cleaning machine in accordance with claim 43, wherein the locking device is connected to the first part and the second part.
 45. Floor cleaning machine in accordance with claim 43, wherein the holder comprises a fastening part which is fixed at the chassis, and comprises an intermediate part which comprises the first part, wherein the intermediate part is oriented at an angle to the fastening part, the intermediate part is in spaced relation to the chassis, and an engagement region at the locking device for an operator is above an upper side or above an underside of the intermediate part.
 46. Floor cleaning machine in accordance with claim 43, wherein the locking device comprises at least one pin element which is in spaced relation to a pivot axis of the pivot joint and is connected to the first part and the second part, wherein a height position of the at least one pin element locks a pivot position of the second part relative to the first part, with at least one of the following: the at least one pin element is formed as an adjusting screw; the at least one pin element is at least one of (i) guided by at least one of the first part and the second part via threads and (ii) provided with a counter nut; a compression spring device is located between the first part and the second part in the region of the at least one pin element and is supported on the first part and the second part.
 47. Method for operating a floor cleaning machine; comprising: a suction unit device; a suction bar which is operatively connectable, or operatively connected, to the suction unit device for fluid communication therewith; a holder which releasably holds the suction bar; a fixing device for releasably fixing the suction bar at the holder; and an overload protection device which is associated with the suction bar; wherein the overload protection device comprises at least one rotational bearing by way of which the suction bar is rotatable at the holder relative to the holder when an overload situation occurs; the method comprising: rotating the suction bar which is held to a holder relative to the holder via the at least one rotational bearing when an overload event occurs. 